Method of increasing power of turbine plants



Aug. 8, 1933. G. E. KERsHAw METHOD OF INCREASING POWER OF TURBINE PLANTS 2 Sheets-Sheet l Filed Jan. 22, 1930 Geary@ E .Kefskv /NI/ENTOR A TT ORNE V Aug. 8, 1933. G. E. KERSHAW A METHODl OF INCREASING POWER OF TURBINE PLANTS Filed Jan. 22, 1930 2 Sheets-Sheet 2 Ge ortie E, Ke rshw.

/NVENTR ATTORNEY PatentedV Aug. 8, v19,33 t

METHOD',

oF INCREASING POWER 0 TURBINE( eLANTs' George E., Kershaw,l East Orange,v N. J assignor to' The-` Superheater Company, New York,

Y VN. Y. y Application January 22,

3 Claims.

My invention relates to turbine power plants and aims to provide a method and apparatus whereby desired increases in horse power4 of existing turbine plants can be obtained'. at. a rela'- tively small cost.`

higher'averag'e speed in ships than was formerly the case; hence many ships are now'foundl-to` have less horse power than required to drive them at the speed giving best commercial returns. If the original power plant of the ship'is forced sufficiently to give Ithe desired speed, the rate of deterioration and the thermallosses usuallybe'-` come excessive, whilev the space available for additions is limited, and a complete new plant is expensive and usually `not economically warranted by the probable life of the shipshull.

I have found, however, that it is possible to Y avoid theA difliculties above4 mentioned and to add largely to thehorse power of the majority of turbine driven-ships in a manner utilizing Y the entire original turbine installation and most of the original boilerjinstallationA but without increasinglthe space allotted tothe power plant of the ship, therebyv obtaining` the needed additional power for increasing the speed Vof thefship to the necessary amount lat a .relatively small cost. r Y It is well known that the majority of turbine driven ships are able todevelop considerably less horse power for going astern than for going ahead. In emergencies, this deficiency is a very seriousmatter and it is an .object ofthe present linvention to provide for increasing 'the horseV` power of existing turbine power plants ina manner that not only requires no space inVV addition to that usually allottedto the ships power plant, but which increases the ratio ofthe astern power to the ahead power. Y

, i The novel features of my invention are pointed out in the appended claims. The invention itself,

however, together with further objects and `ad" vantageswill best be understood from a detailed descriptionvofmyjmethod of enlarging existing turbine power plants and of a power plant ar-` rangement resulting from enlarging the existing plant in accordance with my said method, and such a descriptionwill now be `given in connection with the accompanying drawings illustrate ing aturbine power plant `embodying my in ven tion and in which Y "Fig,v 1 is a diagrammatic view of a power plant whose horse power has been enlarged in accord- Aance with my invention;

p Fig; 2 is an elevationvofla valve arrangementv for controlling steam for the plant according ,to`

Fig. 1; partsbein'g broken awayandv parts being shown in section for'purposes of illustration;

Fig. 3 is a sectionon the line3-3 of Fig. 2

looking in the direction of the arrows.

` inal cross compound'turbinefinstallation comprising' two shafts 10v and 12 coupled by gearing j 1'4fto a propellerjshaft 16. Assuming` that the v Changing commercial conditions demand a`A "installation also Jhad an original low ,pressure` The turbine power *plant whose diagram apv' ahead stage `22 and an original low pressure astern n Ystage24 bothhaving rotorsflxed tofthe shaft l2.`

'Steam at 200 lbs. gaugeforfthe stages 18,*and20 was furnished bythe original s`teamrrainj26 and L controlled by valves 3 and 4for.stag'es 18 and 20 respectively. As isfusual in suchjinstallations, valves 3 and 4 were operated by 'a mechanism insuring that only oneof the valvessuch as3 or 4' would `be Vopened at a time*V When valve 3 opened, steam passed through stage 18 and thence by connectingpipe 28 to low"pressuresta`ge 22ffrom p which it exhausted through line 30 to acondenser,

not-shown. If, however, valve 3lwereclosed`and lvalve 4 opened, 4steam from main 26 would pass-j through the` originalhigh 'pressure astern "stage,` -20 and thence by connecting pipe 32 ,to Vtheoriginal low pressure astern stage '24. From stage` 24 steam could exhaust through pipe 30 tothe con- ,denserQ-j y y 12.*. v f It having become necessary to enlarge thehorse powerA of .the ship or station'coritaining the, original'stages l18, 20, 22 and' 24," onetor moreof wthe lizefthefhigher pressure steam from main, 34 the i l" lahead stagesA 36 and 36a' and the lastern 'stages 38 and 38a are added to the original installation. Stages 36 andV 38 have their rotors fixed to anex- .original boilers furnishing` approximatelyg/gof l tension shaft 40 ,coupled to theoriginal,shaft10, v

as indicated at 42,4 while `stages"36ay vand 38a. have e their rotorsxed to anextensionV shaft 44 shown las coupled tothe original shaft12fat46.Steam for ,the ahead stages 36 and 36a may conveniently ,be taken from frmain.34 through the valve2` from which point it is shown as passing. tothe. stagesl byfpipe `48 having vbranches 50 andrOa. Similarly,steam for the astern stages 38 and 38a may lbe .taken .from mainl 3.4 :through valve V1 from which point it is conducted tothe stages by pipe 52 having branches 54 and'54a connecting to the stages. The original connections between main 261 and stagesV 18 and 20 and the original e connections from stage 18 to stage 22 and from stage 20 to stage 24 are retained in the renovated installation. Y

y rIn the operation of the enlarged installation comprisingstages 36, 36a and'38 and 38a in addition to the original stages 18, 26, 22and 24, during forward running, steam is exhausted from ahead stages 36 and 36a at 200 lbs. and passesl through connecting pipes 56, 56a and 58 to stage 18 where it is used along with steam supplied from the original 200 1b. main 26. Normally, enough steam is l taken at high pressure from main 34 so rthat when exhausted from stages '(36 and 36a it will'supply approximately .1/3 the total steam requirement of ,s`tage, l8. Similarly, duringV reverse running, steam from high pressure main 34 which'is passed through astern stages38 and 38a is exhaustedV at 200 lb. pressure into pipes 66 and 60a from'which it flows through pipe 62 to astern stage 20, stages v38 and 38a being so designed that they'supply 'substantially '1/3 or more ofthe steam required byY stage 20, From stages 18 and 20 the steam passes as before, the piping/between the original stagesbeing kept intact. It will be seen, therefore', that stages 18, 22, 20 and 24 all operate, after the enlargement of the plant, under the same convditi'ons las before, the addition of stages 36, 36a, 38 and 38a acting merely'to increase the output of the plant. 5

It will be seen that astern stages 20 and 24 are of smaller size than ahead stages 18 and k22,*.this

being the usual practice in turbine plants on shipboard. However, I nd that there is usually suij cient space provided in the original engine rooms sothat the astern stages 38 and-88a can be made ofthe same size as the ahead stages'S'and 36a whereby the ratio of the power available for `astern running to that for ahead runningis increased Ywith slight additional expense. e The stages 36 Aand 36a are, of course, both made the same size.

For V controlling Vthe steam tothe enlarged plant AI have'lshown in Figs. 2 and 3 a standard arrangement for operating the valves 1, 2, 3'and `4. The Ivalves are all operated from a single rock shaft 64 having lever arms 66 and 68 projecting from it on `one side for operating valves 2 and I3 respectively and lever arms and `'12 `projecting from it onY the'othen sideV for operating valves 1 and" 4. Each of valves 1 to 4 inclusive has a stem 74 xedV to the valve at one end of the stem, such stem having a collar ,'76 slidable thereon near its'other end. Each collar 76 is coupled to one of the rlevers 6 6, 68, 70,772 by links 78. When the shaft 64 is turned :in thedirection for ahead running, collars 76 for the ahead` valves are raised on the stems 74 and contact with nuts 80 fixed to the upper ends vof the stems so as to raise the corresponding valves. v i If the shaft64 is turned in an opposite direction, the other pair of collars 7.6 for the astern valve are raised Vto `open the corresponding. valves in the same way. The collars 76 are mounted near the e upper ends of the stems Y7.4 and have room to slide downwardly on the stems compressing springs 82 so that when they are forced downwardly by the links '78 no effect is produced and one set of .valves is notaifected when those of the other. set are opened.,A The valves 1, 2,13 and 4 each is normally held closed by a pair of springs 82 and'84. VA'

wheel 86 and Worm gearing 88 is provided forfturn- Ving the shaft 64 in either direction as desired from its neutral position. It has been found economical in packingA and spaceito place the added ahead stages 36 .and 36a adjacent the* original ahead stages 18 and 22 and so that stages 36 and 36a lie between added astern rstages 38 and 38a and original stages 18 and 22.v

While I have described a particular method of' enlarging existing turbine power plants and the ldescribing the relationship between shaft 10 or shaft 12and shaft 16. y

. Further, I do not limit myself to replacing onethird of the original boiler units with higher pressure boilers, since, often one-half,l Vor more,l of

thev original boilers may be so replaced.

, I claim: n

1; A cross compound turbine installation comprising a high pressure forward stage," an intermediate pressure forward stage, ahigh pressure reverse stageV and an Yintermediate pressure reverse stage all driving' on one shaft, a high pressure forward stage, a high pressure'reverse'staga a low pressure forward stage and a'low pressure reverse stagejdriving'on a second shaft, means for supplying steam to said high pressure forward stages during periods of forward running, means for transferring steam which has been used in said high pressure forward stages to said intermediate forward stage, means'for transferring steam which has been used in said intermediate forward stage to said low pressure forward stage,

rparticular varrangement resulting from such enmeans for supplying steam to saidrhigh'pressure Vastern stages during periods of'reverse running, means for'transferring steam vwhich has beenA used in said high pressure astern stages to said yintermediate astern stage and means for transferring steam which has been used in said in-l termediate astern'v stage to said low pressure astern stage. v l

2. A cross compound turbine installationy as set forth in claim 1 together with means for supplyingv additional lsteam of intermediate pressure to the forward intermediate stage when the forward high pressure stages are in action and to the reverse intermediate stage when the vreverse high pressure stages are inaction. e,

3. The combination in a turbine installation of two parallel shafts, a high pressure forward stage and a high pressure reverse stage on each ofv said shafts, an intermediate forwardstage `and an intermediate reverse stage on'one of said shafts,

a low pressure forwardv stage anda low pressure reverse stage o n the other of said shafts, connections forleading steamfrom .-both said high pressure forward stages to saidintermediate forward stage and fromY both said high pressure reverse stages to said intermediate reversestagel and from saidv intermediate stages to said low pressure stages, and an additional intermediate Vsteam supply to said intermediate stages.

GEO. E.- KERsHAw. 

